UM10211 - Standard ICs

NXP Semiconductors
UM10211
Chapter 3: LPC2300 System control
Table 19.
AHB configuration register map
Name Description Access Reset Address
value
AHBCFG1 Configures the AHB1 arbiter. R/W 0 0xE01F C188
AHBCFG2 Configures the AHB2 arbiter. R/W 0 0xE01F C18C
9.1 AHB Arbiter Configuration register 1 (AHBCFG1 - 0xE01F C188)
Table 20. AHB Arbiter Configuration register 1 (AHBCFG1 - address 0xE01F C188) bit
description
Bit Symbol Value Description Reset
value
0 scheduler 0 Priority scheduling. 0
1 Uniform (round-robin) scheduling.
2:1 break_burst 00 Break all defined length bursts (the CPU does not create 00
defined bursts).
01 Break all defined length bursts greater than four-beat.
10 Break all defined length bursts greater than eight-beat.
11 Never break defined length bursts.
3 quantum_type 0 A quantum is an AHB clock. 1
1 A quantum is an AHB bus cycle.
7:4 quantum_size Controls the type of arbitration and the number of quanta
before re-arbitration occurs.
0000 Preemptive, re-arbitrate after 1 AHB quantum.
0001 Preemptive, re-arbitrate after 2 AHB quanta.
0010 Preemptive, re-arbitrate after 4 AHB quanta.
0011 Preemptive, re-arbitrate after 8 AHB quanta.
0100 Preemptive, re-arbitrate after 16 AHB quanta.
0101 Preemptive, re-arbitrate after 32 AHB quanta.
0110 Preemptive, re-arbitrate after 64 AHB quanta.
0111 Preemptive, re-arbitrate after 128 AHB quanta.
1000 Preemptive, re-arbitrate after 256 AHB quanta.
1001 Preemptive, re-arbitrate after 512 AHB quanta.
1010 Preemptive, re-arbitrate after 1024 AHB quanta.
1011 Preemptive, re-arbitrate after 2048 AHB quanta.
1100 Preemptive, re-arbitrate after 4096 AHB quanta.
1101 Preemptive, re-arbitrate after 8192 AHB quanta.
1110 Preemptive, re-arbitrate after 16384 AHB quanta.
1111 Non- preemptive, infinite AHB quanta.
11:8 default_master 0001 Master 1 (CPU) is the default master. 0001
15:12 EP1 0010 External priority for master 1 (CPU) is tbd. tbd
19:16 EP2 0001 External priority for master 2 (AHB1) is tbd. tbd
UM10211_1
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User manual Rev. 01 — 27 March 2007 30 of 613